Lupine Publishers | An archive of organic and inorganic chemical sciences
Abstract
The work is an evolution of research
already begin and in development. Therefore, we can observe a part that has
already been commented that presents the whole development of the research from
its beginning. Preliminary bibliographic studies did not reveal any works with
characteristics studied here. With this arrangement of atoms and employees with
such goals. Going beyond with imagination using quantum chemistry in
calculations to obtain probable one new bio-inorganic molecule, to the Genesis
of a bioinorganic membrane with a combination of the elements Be, Li, Se, Si, C
and H. After calculation a bio-inorganic seed molecule from the previous
combination, it led to the search for a molecule that could carry the structure
of a membrane. From simple molecular dynamics, through classical calculations,
the structure of the molecule was stabilized. An advanced study of quantum
chemistry using ab initio, HF (Hartree-Fock) method in various basis is applied
and the expectation of the stabilization of the Genesis of this bio-inorganic
was promising. The calculations made so far admit a seed molecule at this stage
of the quantum calculations of the arrangement of the elements we have chosen,
obtaining a highly reactive molecule with the shape polar-apolar-polar. Calculations
obtained in the ab initio RHF method, on the set of bases used, indicate that
the simulated molecule, C13H20BeLi2SeSi, is acceptable by
quantum chemistry. Its structure has polarity at its ends, having the
characteristic polar-apolar-polar. Even using a simple base set the
polar-apolar-polar characteristic is predominant. The set of bases used that
have the best compatible, more precise results are CC-pVTZ and 6-311G (3df,
3pd). In the CC-pVTZ base set, the charge density in relation to 6-311G (3df,
3pd) is 50% lower. The structure of the bio-inorganic seed molecule for a
bio-membrane genesis that challenge the current concepts of a protective mantle
structure of a cell such as bio-membrane to date is promising, challenging.
Leaving to the biochemists their experimental synthesis.
Introduction
The
work is an evolution of research already begin and in development. Therefore,
we can observe a part that has already been commented that presents the whole
development of the research from its beginning. A small review of the main
compounds employed some of their known physicochemical and biological
properties and the ab initio methods used. Preliminary bibliographic studies
did not reveal any works with characteristics studied here. With this arrangement
of atoms and employees with such goals. So, the absence of a referential of the
theme. The initial idea was to construct a molecule that was stable, using the
chemical elements Lithium, Beryllium, alkaline and alkaline earth metals,
respectively, as electropositive and electronegative elements - Selenium and
Silicon, semimetal and nonmetal, respectively. This molecule would be the basis
of the structure of a crystal, whose structure was constructed only with the
selected elements. The elements Li, Be, Se and Si were chosen due to their
physicochemical properties, and their use in several areas of technology [1-4].
To construct such a molecule, which was called a seed molecule, quantum
chemistry was used by ab initio methods [5,6,7]. The equipment used was a
cluster of the Biophysics laboratory built specifically for this task. It was
simulated computationally via molecular dynamics, initially using Molecular
Mechanics [8-24] and ab initio methods [5,6,7]. The results were satisfactory.
We found a probable seed molecule of the BeLi2SeSi structure predicted by
quantum chemistry [23]. Due to its geometry, it presents a probable formation
of a crystal with the tetrahedral and hexahedral crystal structure [23].
The
idea of a new molecule for a crystal has been upgraded. Why not build a
molecule, in the form of a lyotropic liquid crystal [25] that could be the
basis of a new bio-membrane? For this, the molecule should be amphiphilic, with
polar head and apolar tail. Are basic requirement of the construction of a bio-membrane
[25]. Then it is necessary to add a hydrophobic tail, with atoms of carbon and
hydrogen. Therefore, the molecule seed with a polar hydrophilic “head”. So,
would a new amphiphilic molecule. Several simulations were performed, always
having as initial dynamics the use of Molecular Mechanics [8-24] for the
initial molecular structure, moving to ab initio calculations of quantum
chemistry. All attempts were thwarted. Quantum calculations of quantum
chemistry did not accept the seed molecule as the polar head, even changing its
binding structure. The silicon atom binds in double bond with the carbon chain
and Selenium. It binds in double with beryllium and is simple with the two
lithium atoms, thus making a stable molecular structure for Molecular Mechanics
[8-24], Mm+ and Bio+ Charmm [26]. But in quantum calculations the seed molecule
changed all its fundamental structure [1]. The linear structure of the tail
with the polar head, in the form of a rope climbing hook, collapsed, bending
toward a polar tail. In another simulation carried out the Selenium was
connected in double bond to two atoms of Carbon added in double bond. As the +6
polarities of the selenium neutralized with the atoms two atoms of lithium,
forming a wing. In the double bonded sequence is the Carbon with the Silicon,
and this in double bond with the Beryllium. A new structure for a probable
lyotropic liquid crystal has now been formed. A polar tail with the seed
molecule undone but retaining the five base atoms of its fundamental structure
[25]. The structure after Molecular Mechanics, Mm+ and Bio+ Charmm [26], the
shape of the molecule obtained had a structure like a boomerang. After
calculations ab initio, the polar tail was undone. The Beryllium atom did not
remain in the structure of the molecule, releasing itself from it. There is
then a new idea. Why not separate the electropositive and electronegative
elements in two polar heads? This would completely change the concepts known so
far of a biomembrane with a lipid bilayer. The next challenging step of
building a bio-membrane that runs away from known concepts, with a single
layer, with two polar heads and its non-polar backbone. Would it be a new way
to have a bio-membrane? A challenge for quantum chemistry.
Then
he concentrated the calculations on the probable structure of the molecule with
polar ends. Separately then in pairs the atoms of Selenium with Beryllium and
Silicon with the two bonds. Again, the attempt failed, in quantum calculations.
Beryllium was disconnected from the basic structure of the new molecule,
polarpolar- polar polar structure. They have decided to further innovate the
theory and “challenge” quantum chemistry. Add an aromatic ring to the polar
head. The polar-polar-polar linear structure was now maintained, with a
six-carbon cyclic chain. At a polar end, the Silicon is bonded to three atoms
of the Hydrogen and is connected to a Carbon from the central chain. This one
connected to the two atoms of the Lithium and a polar central carbon chain. At
the other polar end, the six-carbon cyclic chain attached in single bond to the
carbonic chain. The cyclic chain with simple bonds, having at its center the
Selenium with six bonds to the cyclic chain and a double with the Beryllium,
thus forcing two more covalent bonds. Now with a +2 cationic head, the dynamics
of the minimization energy with Mm+ and Bio+ Charmm [26] calculations have
maintained a stable structure of the molecule. A polar head like a “parabolic
antenna”, with folded edges outward with the Hydrogen atoms. The expected, the
obvious, Beryllium playing the role of the “LNB (Low Noise Block) receiver”. We
then proceeded to the ab initio calculations in several methods and basis,
testing various possibilities with ab initio methods. The polar-apolar-polar
(parabolic) molecule in ab initio calculation, by RHF [5-6,27-32] in the TZV
[33,34] sets basis was shown to be stable by changing its covalent cyclic chain
linkages, which was expected, (Figure 2). The set of bases used was that of
Ahlrichs and coworker’s main utility are: the SV, SVP, TZV, TZVP keywords refer
to the initial formations of the split valence and triple zeta basis sets from
this group [33,34]. Calculations continue to challenge concepts, experimenting.
Going where imagination can lead us, getting results that challenge concepts.
Chemical Properties of the Compounds of Beryllium, Lithium,
Selenium and Silicon
Go to
The
Beryllium, Lithium, Selenium and Silicon elements were chosen due to their
peculiar physicochemical properties and their wide use in industry, technology,
life, health.
Beryllium
Beryllium
is created through stellar nucleosynthesis and is a relatively rare element in
the universe. It is a divalent element which occurs naturally only in
combination with other elements in minerals. Notable gemstones which contain
beryllium include beryl (aquamarine, emerald) and chrysoberyl. As a free
element it is a steel-gray, strong, lightweight and brittle alkaline earth
metal [2]. Beryllium improves many physical properties when added as an alloying
element to aluminium, copper (notably the alloy beryllium copper), iron and
nickel. Tools made of beryllium copper alloys are strong and hard and do not
create sparks when they strike a steel surface. In structural applications, the
combination of high flexural rigidity, thermal stability, thermal conductivity
and low density (1.85 times that of water) make beryllium metal a desirable
aerospace material for aircraft components, missiles, spacecraft, and
satellites. Because of its low density and atomic mass, beryllium is relatively
transparent to X-rays and other forms of ionizing radiation; therefore, it is
the most common window material for X-ray equipment and components of particle
physics experiments [2,35]. Beryllium is a health and safety issue for workers.
Exposure to beryllium in the workplace can lead to a sensitization immune
response and can over time develop chronic beryllium disease (CBD) [37].
Approximately 35 micrograms of beryllium are found in the average human body,
an amount not considered harmful [38]. Beryllium is chemically like magnesium
and therefore can displace it from enzymes, which causes them to malfunction
[38]. Because Be2+ is a highly charged and small ion, it can easily get into
many tissues and cells, where it specifically targets cell nuclei, inhibiting
many enzymes, including those used for synthesizing DNA. Its toxicity is
exacerbated by the fact that the body has no means to control beryllium levels,
and once inside the body the beryllium cannot be removed [39]. Chronic berylliosis
is a pulmonary and systemic granulomatous disease caused by inhalation of dust
or fumes contaminated with beryllium; either large amounts over a short time or
small amounts over a long time can lead to this ailment. Symptoms of the
disease can take up to five years to develop; about a third of patients with it
die and the survivors are left disabled [38]. The International Agency for
Research on Cancer (IARC) lists beryllium and beryllium compounds as Category 1
carcinogens. In the US, the Occupational Safety and Health Administration
(OSHA) has designated apermissible exposure limit (PEL) in the workplace with a
timeweighted average (TWA) 0.002 mg/m3 and a constant exposure limit of 0.005
mg/m3 over 30 minutes, with a maximum peak limit of 0.025 mg/m3. The National
Institute for Occupational Safety and Health (NIOSH) has set a recommended
exposure limit (REL) of constant 0.0005 mg/m3. The IDLH(immediately dangerous
to life and health) value is 4 mg/m3 [40].
Lithium
Lithium
like all alkali metals, lithium is highly reactive and flammable. Because of
its high reactivity, lithium never occurs freely in nature, and instead, only
appears in compounds, which are usually ionic. Lithium occurs in a number of
pegmatitic minerals, but due to its solubility as an ion, is present in ocean
water and is commonly obtained from brines and clays [2]. Lithium and its
compounds have several industrial applications, including heat-resistant glass
and ceramics, lithium grease lubricants, flux additives for iron, steel and
aluminum production, lithium batteries and lithium-ion batteries [2]. As
lithium salts, are primarily used as a psychiatric medication. This includes
the treatment of major depressive disorder that does not improve following the
use of other antidepressants, and bipolar disorder [41]. In these disorders, it
reduces the risk of suicide [42]. Common side effects include increased
urination, shakiness of the hands, and increased thirst. Serious side effects
include hypothyroidism, diabetes insipidus, and lithium toxicity. Blood level
monitoring is recommended to decrease the risk of potential toxicity. If levels
become too high, diarrhea, vomiting, poor coordination, sleepiness, and ringing
in the ears may occur. If used during pregnancy, lithium can cause problems in
the baby [42]. In the nineteenth century, lithium was used in people who had
gout, epilepsy, and cancer. Its use in the treatment of mental disorder began
in 1948 by John Cade in Australia [43]. It is on the World Health
Organization’s List of Essential Medicines, the most effective and safe
medicines needed in a health system [44].
Selenium
Selenium
is found impurely in metal sulfide ores, copper where it partially replaces the
sulfur. The chief commercial uses for selenium today are in glassmaking and in
pigments. Selenium is a semiconductor and is used in photocells. Uses in
electronics, once important, have been mostly supplanted by silicon
semiconductor devices. Selenium continues to be used in a few types of DC power
surge protectors and one type of fluorescent quantum dot [2]. Although it is
toxic in large doses, selenium is an essential micronutrient for animals. In
plants, it sometimes occurs in toxic amounts as forage, e.g. locoweed. Selenium
is a component of the amino acids selenocys teine and selenomethionine. In
humans, selenium is a trace element nutrient that functions as cofactor for
glutathione peroxidases and certain forms ofthioredoxin reductase [45].
Selenium-containing proteins are produced from inorganic selenium via the intermediacy
of selenophosphate (PSeO3 3−). Selenium is an essential micronutrient in
mammals but is also recognized as toxic in excess. Selenium exerts its
biological functions through selenoproteins, which contain the amino acid
selenocysteine. Twenty-five selenoproteins are encoded in the human genome
[46]. Selenium also plays a role in the functioning of the thyroid gland. It
participates as a cofactor for the three thyroid hormonedeiodinases. These
enzymes activate and then deactivate various thyroid hormones and their
metabolites [47]. It may inhibit Hashimotos’s disease, an auto-immune disease
in which the body’s own thyroid cells are attacked by the immune system. A
reduction of 21% on TPO antibodies was reported with the dietary intake of 0.2
mg of selenium [48]. Selenium deficiency can occur in patients with severely
compromised intestinal function, those undergoing total parenteral nutrition,
and [49] in those of advanced age (over 90).
Silicon
Silicon
is the eighth most common element in the universe by mass, but very rarely
occurs as the pure free element in nature. It is most widely distributed in
dusts, sands, planetoids, and planets as various forms of silicon dioxide
(silica) or silicates. Over 90% of the Earth’s crust is composed of silicate
minerals, making silicon the second most abundant element in the Earth’s crust
(about 28% by mass) after oxygen [11]. Elemental silicon also has a large
impact on the modern world economy. Although most free silicon is used in the
steel refining, aluminium-casting, and fine chemical industries (often to make
fumed silica), the relatively small portion of very highly purified silicon
that is used in semiconductor electronics (<10%) is perhaps even more critical.
Because of wide use of silicon in integrated circuits, the basis of most
computers, a great deal of modern technology depends on it [2]. Although
silicon is readily available in the form of silicates, very few organisms use
it directly. Diatoms, radiolaria and siliceous sponges use biogenic silica as a
structural material for skeletons. In more advanced plants, the silica
phytoliths (opal phytoliths) are rigid microscopic bodies occurring in the
cell; some plants, for example rice, need silicon for their growth [50,51,52].
There is some evidence that silicon is important to nail, hair, bone and skin
health in humans, [53] for example in studies that show that premenopausal
women with higher dietary silicon intake have higher bone density, and that silicon
supplementation can increase bone volume and density in patients with
osteoporosis [54]. Silicon is needed for synthesis of elastin and collagen, of
which the aorta contains the greatest quantity in the human body [55] and has
been considered an essential element [56].
Methods
Molecular dynamics
In
short, the goal of molecular mechanics is to predict the detailed structure and
physical properties of molecules. Examples of physical properties that can be
calculated include enthalpies of formation, entropies, dipole moments, and
strain energies. Molecular mechanics calculates the energy of a molecule and
then adjusts the energy through changes in bond lengths and angles to obtain
the minimum energy structure [8-24].
The steric energy, bond stretching, bending, stretch-bend, out of plane, and torsion interactions are called bonded interactions because the atoms involved must be directly bonded or bonded to a common atom. The van der Waals and electrostatic (qq) interactions are between non-bonded atoms [8-24].
Hartree-Fock
The
Hartree-Fock self–consistent method [5-6,27- 32] is based on the one-electron
approximation in which the motion of each electron in the effective field of
all the other electrons is governed by a one-particle Schrodinger¨ equation.
The Hartree- Fock approximation considers of the correlation arising due to the
electrons of the same spin, however, the motion of the electrons of the
opposite spin remains uncorrelated in this approximation. The methods beyond
self-consistent field methods, which treat the phenomenon associated with the
many-electron system properly, are known as the electron correlation methods.
One of the approaches to electron correlation is the Møller-Plesset (MP)
[5,6,57,58] perturbation theory in which the Hartree-Fock energy is improved by
obtaining a perturbation expansion for the correlation energy [5]. However, MP
calculations are not variational and can produce an energy value below the true
energy [6]. The exchangecorrelation energy is expressed, at least formally, as
a functional of the resulting electron density distribution, and the electronic
states are solved for self-consistently as in the Hartree-Fock approximation
[27-30]. A hybrid exchange-correlation functional is usually constructed as a
linear combination of the Hartree-Fock exact exchange functional,
and any number of exchange and correlation explicit density functional. The parameters determining the weight of each individual functional are typically specified by fitting the functional predictions to experimental or accurately calculated thermochemical data, although in the case of the “adiabatic connection functional” the weights can be set a priori [32]. Terms like “Hartree-Fock”, or “correlation energy” have specific meanings and are pervasive in the literature [59]. The vast literature associated with these methods suggests that the following is a plausible hierarchy:
The extremes of ‘best’, FCI, and ‘worst’, HF, are irrefutable, but the intermediate methods are less clear and depend on the type of chemical problem being addressed [4]. The use of HF in the case of FCI was due to the computational cost.
For calculations a cluster of six
computer models was used: Prescott-256 Celeron © D processors [2], featuring
double the L1 cache (16 KB) and L2 cache (256 KB), Socket 478 clock speeds of
2.13 GHz; Memory DDR2 PC4200 512MB; Hitachi HDS728080PLAT20 80 GB and CD-R. The
dynamic was held in Molecular Mechanics Force Field (Mm+), Equation (1), after
the quantum computation was optimized via Mm+ and then by RHF [5-6,27-32], in
the TZV [33,34] sets basis. The molecular dynamics at algorithm Polak- Ribiere
[60], conjugate gradient, at the termination condition: RMS gradient [61] of 0,
1kcal/A. mol or 405 maximum cycles in vacuum [6,41]. The first principles
calculations have been performed to study the equilibrium configuration of C13H20BeLi2SeSi molecule using the
Hyperchem 7.5 Evaluation [41], Mercury 3.8 a general molecular and electronic
structure processing program [18], GaussView 5.0.8 [64] an advanced semantic
chemical editor, visualization, and analysis platform and GAMESS is a
computational chemistry software program and stands for General Atomic and
Molecular Electronic Structure System [7] set of programs. The first principles
approaches can be classified in the Restrict Hartree-Fock [5-6,27-32] approach.
Discussions
The
Figure 2 shows the final stable structure of the Bioinorganic molecule obtained
by an ab initio calculation with the method RHF [5-6,27-32], in several sets of
basis such as: STO-3G [7,30,60,71,83,84, 85,86]; 3-21G
[7,30,60,71,83,84,85,86]; 6-31G [7,30,60,71,83,84,85,86]; 6-31(d’)
[7,30,60,71,83,84,85,86]; 6-31(d’,p’) [7,30,60,71,83,84,85,86]; 6-311G
[7,30,60,71,83,84,85,86]; 6-311G(3df,3pd) [7,30,60,71,83, 84,85,86]; SV
[81,82]; SDF [71,72]; SDD [71,72]; SDDAll [71,72]; TZV [81,82]; CC-pVDZ
[66,67,68,69,70]; CC-pVTZ [66-70]; CEP- 31G [66-70]; CEP-121G [66-70]; LanL2DZ
[71,78,79,80]; LanL2MB [71,78,79,80], starting from the molecular structure of
(Figure 1) obtained through a molecular mechanical calculation, method Mm+ and
Bio+ Charmm [8-24,26,65].
The molecular structure shown in Figure 2
of the bio-inorganic molecule C13H20BeLi2SeSi, is represented in structure in the
form of the van der Walls radius [4,5,6]. As an example of analysis, the set of
bases TZV [81,82]. with the charge distribution (Δδ) through it, whose charge
variation is Δδ = 4.686 au of elemental charge. In green color the intensity of
positive charge displacement. In red color the negative charge displacement
intensity. Variable, therefore, of δ- = 2,343 a.u. negative charge, passing through
the absence of charge displacement, represented in the absence of black - for
the green color of δ+ = 2.343 a.u. positive charge. The electric dipole moment
() total obtained was p = 5.5839 Debye, perpendicular to the main axis of the
molecule, for sets basis TZV [81,82]. By the distribution of charge through the
bio-inorganic molecule it is clear that the molecule has a polar-apolar-polar
structure, with neutral charge distributed on its main axis, the carbonic
chain. A strong positive charge displacement (cation) at the polar ends of the
molecule, in the two lithium and silicon atoms, bound to the carbon atom with
strong negative (anion). Therefore, there is a displacement of electrons from
the two lithium and silicon atoms towards the carbon attached to them. At the
other end of the cyclic chain, attached to it is the totally neutral Selenium
atom, while the beryllium is extremely charged with positive charge (cationic),
represented in green color. While the two carbon atoms of the cyclic chain connected
to Beryllium, with negatively charged (anionic), represented in red color. It
happened, therefore, a displacement of electrons of the Beryllium atom towards
the Carbons connected to it. An analysis of the individual charge value of each
atom of the molecule could be made, but here it was presented only according to
(Figure 2), due to the objective being to determine the polarpolar- polar, the
polar characteristic of the molecule, whose moment of dipole is practically
perpendicular to the central axis of the molecule. In Figure 2 the dipole
moment is visualized in all the base sets, being represented by an arrow in
dark blue color, with their respective values in Debye. This also presents the
orientation axes x, y and z and the distribution of electric charges through
the molecule. Analyzing the charge distribution through the molecule.
In
all the sets of bases used, the Silicon atom presents a strong positive charge,
that is, cationic form, represented in green color, except for the LanL2MB
base, which presents a strong negative charge displacement, represented in red
color. The two Lithium atoms accompany the cationic tendency of Silicon, but
with less intensity. The Carbon atom connected to the central chain, and to
Silicon and the two Lithiums, presents a strong negative charge, that is,
anionic form, represented in red color. There is, therefore, a shift of the
electric charges of the silicon atom and of the two Lithiums towards the
Carbon. This charge displacement is evident in all the base sets studied,
except for the base STO-3G and LanL2MB, which present almost neutral charge for
the said Carbon atom.
The backbone of the molecule, that is,
its central axis which has a chain of seven aligned Carbon atoms, has a
homogeneous charge distribution, with approximately neutral polarity,
represented by the absence of color (black). This charge neutrality is observed
in the set of bases: STO-3G; 6-31 (d ‘, p’); TZV; SDD; CEP-31G; CCcVDZ; SV and
CEP-121G. In the set of bases: 3-21G; 6-31G; 6-31 (d ‘); 6-311G; SDF; LanL2DZ
and LanL2MB, the central axis of the molecule has a small distribution of
negative charge throughout its length, due to the negative charge displacement
of Hydrogen atoms (seen slightly in blackish green, tending to black) connected
to each of their respective Carbon atoms, whose charge is slightly negative
(visualized in blackish red color, tending to black). At the other end of the
molecule is the cyclic chain of six Carbon atoms. Which has only one double
connection. The cyclic chain is attached to the Beryllium atom and to two
Carbon atoms, symmetrical and central to the cyclic chain. The Selenium atom is
connected to two carbon atoms of the cyclic chain, the first Carbon atom being
connected to the central axis of the molecule and the second atoms in sequence,
being opposed to the double bonded cyclic chain atoms. The Beryllium atom
presents a strong positive charge, cationic character, visualized in green
color, in the set of bases: 3-21G; 6-31G; 6-311G; 6-311G (3df, 3pd); SV and
TZV. Beryllium presents almost totally neutral charge in the set of bases: 6-31
(d ‘); 6-31 (d, p ‘); CC-pVDZ; cc-pVTZ; CEP-31G and CEP-121G. And charge,
slightly positive in another basis studied. The Selenium atom is visualized in
Figure 2, as seen always behind the cyclic chain. This presents a neutral
charge distribution in all basis studied, with the exception of CCpVTZ and
LanL2MB. The Table 1 presents the Molecular parameters of the atoms of the
molecule C13H20BeLi2SeSi seed, obtained
through computer via ab initio calculation method RHF [5-6,27-32] in base
6-311G**(3df,3pd) [7,30,60,71,83,84,85], obtained using computer programs
GAMESS [7]. end software [64], (Figure 1) the right. The distance between the
atoms is measured in Ångstron, as well as the position of the atoms in the
coordinate axes x, y and z. The angles formed, and the angles formed in the
dihedral are given in degrees. In the Table 2 containing the electric dipole
moments, in the directions of the coordinate axes axes x, y and z, given in
Debye, are presented in all the sets of bases studied. The minimum and maximum
charge distributed through the molecule and the variation of the charge (in
a.u.) by the extension of the molecule (C13H20BeLi2SeSi). They are represented by the
variation of the intensities of the green color (positive charge), through
black (zero charge) and red (negative charge), evenly distributed according to
the basic functions used in quantum calculations allowed by quantum chemistry.
The largest distributed charge variation (Δδ) per molecule was calculated on
the base set TZV, with Δδ = 4.686 a.u., and the lowest in the CC-pVTZ set, with
Δδ = 0.680 a.u., (Table 2). The highest total electric dipole moment () was
obtained using the CEP-31G method, with p = 6.0436 Debye, with Δδ = 1.860 a.u.,
and the lowest electric dipole moment in the STO-3G method, with p = 4.2492
Debye, with Δδ = 1.510 a.u.
Conclusion
Calculations obtained in the ab initio
RHF method, on the set of bases used, indicate that the simulated molecule, C13H20BeLi2SeSi, is acceptable by
quantum chemistry. Its structure has polarity at its ends, having the
characteristic polar-apolar-polar. Even using a simple base set the
polar-apolar-polar characteristic is predominant. From the set of bases used in
the RHF, based on 6-311G (3df, 3pd), the Silicon atoms, the two Lithium, have a
strong density of positive charge, cationic, from the displacement of charges
of these atoms towards the atom which Carbon are connected, which consequently
exhibits strong negative charge density, anionic. It is observed a cyclic
displacement and constant electric charges originating from the sp orbitals of
the Carbon atom, (Figure 2). At the other end of the molecule, a similar
situation occurs. The Beryllium atom presents a high density of positive
charge, cationic character, due to the displacement of the electronic cloud of
that one towards the Carbon atoms that is connected. These Carbon atoms also
receive a displacement of negative charges, originating from the two Carbon
atoms that are linked in the cyclic chain, in covalent double bonds. Now
presenting these latter a strong density of positive, cationic charges, such as
Beryllium, leaving the anionic Beryllium bound Carbon. The Selenium atom has a
small anionic character. Among all simulated base assemblies, 6-311G (3df,
3pd), is unique that exhibits the characteristic of the central chain, with a
small density of negative charges, near the ends of the Carbons of this.
In
the CC-pVTZ base set, the charge density in relation to 6-311G (3df, 3pd) is
50% lower, with characteristics like those shown in the Silicon and the two
Lithium atoms. However, the central chain presents an anionic feature, for all
its extension, originating from the displacement of charges of the Hydrogen
atoms connected to them. At the other end of the cyclic chain, the Selenium
atom presents high density of negative charges, anionic, as well as in the
cyclic chain the Carbon atoms present anionic characteristics, with little
intensity, distributed proportionally by these atoms, originating from the
displacement of charges of the Hydrogens linked to these. Except for the Carbon
atom, connected to the central axis of the molecule that is not bound to
Hydrogens atoms. The structure of the Bio-inorganic seed molecule for a
bio-membrane genesis that defies the current concepts of a protective mantle
structure of a cell such as bio-membrane to date is promising, challenging.
Leaving to the Biochemists their experimental synthesis. The quantum
calculations must continue to obtain the structure of the bioinorganic
bio-membrane. The following calculations, which are the computational simulation
via Mm+, QM/MM, should indicate what type of structure should form. Structures
of a liquid crystal such as a new membrane may occur, micelles.
https://lupinepublishers.com/chemistry-journal/pdf/AOICS.MS.ID.000167.pdf
https://lupinepublishers.com/chemistry-journal/fulltext/the-creation-of-c13h20beli2sesi.-the-proposal-of-a-bio-inorganic-molecule-using-ab-initio-methods-for-the-genesis-of-a-nano-membrane.ID.000167.php
For more Lupine Publishers Open Access Journals Please visit our
website: https://lupinepublishersgroup.com/
For more Open
Access Journal on Chemistry articles Please Click Here:
https://lupinepublishers.com/chemistry-journal/
To Know More About Open Access Publishers Please Click on Lupine Publishers
Follow on Linkedin : https://www.linkedin.com/company/lupinepublishers
Follow on Twitter : https://twitter.com/lupine_online
No comments:
Post a Comment